WODY PODZIEMNE ZRĘBU ZAKRZÓWKA (Wyżyna Krakowsko-Częstochowska) (z 26 fig.)

Abstract

THE GROUNDWATER OF ZAKRZÓWEK HORST (S Kraków-Częstochowa Upland) (with 26 Figs.)Abstract. Basing on the analyses of chloride concentrations in the Vistula River and in 25 selected outflows in the Zakrzówek Quarry carried on systematically during almost three years (1990–93), the shortest time measured for water transfer from river to the quarry was about 100–120 days. Average TDS of river waters in this period was about 2750 milligrams per litre with dominating chloride and sodium ions. Simultaneously, meteoric waters analysed during those three years showed TDS up to 130 milligrams per litre with dominating calcium, magnesium and sulphide ions. In the quarry outflows the TDS varied from 620 to over 2000 milligrams per litre. In a few sampling points located in the northern part of the pit (i.e. close to the river bed) chloride and sodium ions predominated whereas waters from other points contained chloride and sodium along with calcium, magnesium, sulphates and hydrocarbonate ones. Decreasing TDS was accompanied by increasing percentage of sulphates, calcium and magnesium, and then HCO3 in the TDS. Transformation of chemical composition of waters migrating from the Vistula River to the Zakrzówek Quarry consists mainly of changes in concentrations of various ions. In most of the studied outflows waters are enriched in calcium and sulphates, and, in a few points, also in magnesium and potassium. This may result from leaching of these elements in waterbeds and also from ion exchange (e.g. Na–Ca). Concentrations of other pollutants originating from agriculture, sewages and industrial sources decrease on the way from river to quarry. Characteristic is the evolution of nitrogen compounds. Concentrations of ammonium nitrogen in the river waters are higher than in the quarry outflows due to nitrification processes. On the contrary, contents of nitrates are higher in most of quarry outflows than in river waters. Generally, the quality of water improves during migration from river to the quarry.